Leases (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Nov. 30, 2019	Nov. 30, 2019	Jun. 01, 2019
Leases [Abstract]
Total lease costs	$ 15.5	$ 31.0
Operating lease costs	12.6	25.4
Short-term lease costs	0.7	1.2
Variable lease costs	2.2	4.4
Supply Arrangement Variable Lease Costs	23.8	45.7
2020	24.8	24.8
2021	47.6	47.6
2022	44.0	44.0
2023	39.6	39.6
2024	33.9	33.9
Thereafter	102.0	102.0
Total lease payments	291.9	291.9
Less interest	30.0	30.0
Present value of lease liabilities	261.9	261.9
Leases Not yet Commenced Future Payments	25.4	25.4
Lease liabilities, noncurrent	$ 198.1	$ 198.1	$ 0.0
2020			51.7
2021			46.8
2022			42.9
2023			39.0
2024			33.5
Thereafter			101.9
Total			$ 315.8
Weighted Average Remaining Lease Term	7 years	7 years
Weighted Average Discount Rate, Percent	3.10%	3.10%
Cash paid for amounts included in the measurement of lease liabilities	$ 13.3	$ 25.8
Right-of-use assets obtained in exchange for operating lease liabilities	$ 4.0	$ 8.6

Legally binding future minimum lease payments for lessee's operating lease that has not yet commenced.

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Amount of variable leases costs, excluded from lease liability, related to raw meterial purchases under certain supply arrangements that the Company has determined to meet the definition of a lease.

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Amount of lease cost recognized by lessee for lease contract.

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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